To verify and test radio network deployment and operation, drive tests have been conducted in the past. Drive testing typically involves the use of specific measurement tools that could be driven or carried through an area to collect data for network operation verification. Thus, manual testing and verification of radio network operation has been common. For existing and especially for newer networks (e.g. LTE and future networks), it is desirable to reduce the need for drive testing or walk testing to reduce manual testing of networks and therefore reduce operational costs. Accordingly, studies regarding support for minimization of drive tests (MDT) are currently popular which aim to utilize commercial terminals for reporting of relevant measurement results in order to avoid separate manual testing with special test equipments and involvement of operator personnel.
MDT feature enables UEs to perform Operations, Administration, and Maintenance (OAM) activities, such as neighborhood detection, measurements, logging and recording for OAM purposes, which includes radio resource management (RRM) and optimization purposes. There are two types of MDT. For immediate MDT, measurements are performed by the UEs in CONNECTED state for E-UTRA. The collected information is either measured directly in the network or measured in the UE and reported to the network immediately as it becomes available. For logged MDT, measurements are performed and logged by the UEs in IDLE state for E-UTRA. The UEs may report the collected and logged information to the network at a later point of time.
The UE collected measurement information during MDT, in general, may contain location information of the user, or may contain data from which location of the user can be estimated. The location information related to MDT measurements is often highly valuable. For example, the ability to determine that many radio link failures are occurring in a small area of a network cell can allow localized corrective actions that improve quality of service in the small area. MDT thus creates a need for an efficient and active location acquisition control scheme governing how location information related to MDT measurements is acquired.
In current 3GPP systems, the only location option supported is “best effort” location, meaning that UE will attach detail location information (latitude, longitude) if it is available in UE. One problem with the current art is that the nature of the control interface between MDT and location features is still not explored. As there are many flavors of positioning, e.g., U-Plane location as defined by OMA, C-Plane LCS by 3GPP, UE internal positioning, and a number of different positioning methods, the problem of how to control positioning is not trivial. In current 3GPP radio access systems, there is no feature for which it is needed to do selection of LCS systems and UE stand-alone location. Furthermore, the entities that can do UE selection for MDT are largely unaware of UE capabilities with respect to location. For example, eNB and OAM do not know UE capabilities, and RNC can know C-Plane LCS capabilities, but does not know U-Plane LCS capabilities. Therefore, it is difficult to perform location option control in an efficient way.
It is an objective of the current invention to provide a novel design that addresses the problems of prior art. It is an objective to propose solutions for addressing the non-knowledge of location related capabilities. It is an objective to propose a general set of information elements to control the selection of location options for MDT that is future-proof, and to maximizes the reuse of existing positioning functionality that ties together the current MDT best effort location concept, the on-demand/requested location concept, and the enhanced best effort location.
Location information is not only important to MDT measurements, but also an important feature for mobile users. In addition to cellular networks, there are other networks able to deliver location information to mobile users. In most geographic areas, multiple radio access networks (RANs) such as E-UTRAN and wireless local area network (WLAN) are usually available. Furthermore, wireless communication devices are increasingly being equipped with multiple radio transceivers for accessing different radio access networks. For example, a multiple radio terminal (MRT) may simultaneously include Bluetooth, LTE, and WiFi radio transceivers. Accordingly, more positioning methods become available to UE. Among the various positioning methods, UE has the knowledge to choose the best positioning method before the network is involved. It is another objective of the current invention to utilize the characteristics of a network condition in determining the best positioning procedure.